I can confirm that we have not made any changes with how we locate the elements during recording. Please send us a screen shot or record a Jing video that demonstrates you are able to see AutomationID with an older version of Test Studio. A screen shot showing our DOM tree with your AutomationID's visible would be very helpful in diagnosing this problem.
In general the AutomationID either exists or not. It does not depend on the version of Test Studio.
You can record also a Fiddler trace using FiddlerCap and send it to us in a zip file. We can try to "simulate" your app in order to reproduce the problem locally.
Hope to hear from you soon.
the Telerik team